Dry powder fire extinguisher



March 19, 1957 J. B. FLEMING ETAL 2,785,760

DRY POWDER FIRE EXTINGUISHER Filed March 5, 1955 I 2 Sheets-Sheet i ATTORNEY.

March 19, 1957 J. B. FLEMING ETAL DRY POWDER FIRE EXTINGUISHER Filed March 3, 1955 2 Shgets-Sheet 2 MUN E M W K 4 5d U d a es, atchtiQv i 2,785,760 I DRY rownnn FIRE EXTINGUISHER Jere B. Fleming and B; Fleming, New York, N. Y.

Application March s, 1955, Serial no; 491,851

2 Claims. Cl. 169-31 This invention relates to a' dry powder fire extinguisher and more panicularly to a diaphragm type of fire extinguisher having a depressible valve plunger provided withacuttingedge. p i

- It is anobjective of this invention to provide a dry powder fire extinguisher of inexpensive construction;

It is another objective to provide a high pressure dry 1 the fire extinguisher cap showing abayonetslot-in-a depending wall offsaid cap,

1 Fig. 4 is afrontview showing the cap'in closedposition and showing in dotted outline cap in the open or operative positive,

Fig. 5 is a longitudinal section view of the extinguisher valve head assembly showing the plunger disposed in cut-through relationship to the sealing diaphragm,

Fig. 6 is a fragmentary view cut-through portion of the extinguisher of Fig. 5 but taken at right angles thereto,

Fig. 7 is a cross section view of a modified dry powder fire extinguisher showing a squeeze grip means for actuating the valve plunger and Fig. 8 is a view taken on line 8-8 ofFig. 7.

The dry powder fire extinguisher of this invention employs a high pressure resistant container 10 which is provided with an inlet gas valve 11 such as is used on automobile tire tubes and a high pressure gauge 12. The dry powder fire extinguisher material used is powdered sodium bicarbonate, and the high pressure in the container 10 is preferably obtained with nitrogen gas, but other inert gases at about 150 pounds per square inch are operable.

The container 10 is provided with a mouthin its top curvatured portion into which there is fixedly disposed as by welding thereto, a threaded tubular valve seat 13. The valve seat 13 is provided with a circular shoulder 14 upon which there is disposed a syphon tube 15 having a perpendicularly disposed flange 16X.

A sealing diaphragm 16 of suitable metal thickness and pierceable quality is disposed on the flange l4 and an O-ring 17 is disposed upon the diaphragm 16 adjacent the rim thereof.

A screw threaded tubular valve plug 18 is provided with screws threads 19 adapted to engage the mating screw threads of valve seat 13. The passage of plug 18 is provided with a tubular plunger 20 moveably disposed therein. The plunger 20 is provided with a cutting edge 21 on a beveled terminal end having preferably a lesser diameter than that of the main section of passage 20.

2,785,760 Patented Mar. 1 19975? The plunger 20 is-fixedly secured to a cap 22 having a partial depending skirt 23. f 3

The skirt 23 of cap 22. is provided with 'ahor'izontal slot merging at its right end with a'vertical slotto' pro: vide a bayonet slot 24. The plunger 20 is providedfwith a slot 25 suitably disposed relative to the ba onerslerug The plug 18 is provided with an exit orifice'26 in which, a n0zzle'27'having a flattened port isfixedly'disposed by press fitting therein. The-fire extinguisher. is further provided with a handle 28 of U-shaped cross-section fixedly secured as by welding to plug18.; t J

- Figs. 2 to 4 show the valve inithefnon-operative 'position having an unpunctured sea1ingdisk'16JTo eperate; the valve cap 22;which'is normally tapeddowiifivitli friction tape (not shown) the tape'is ripped on the.

} bayonet slot 24 (Fig. 4) (dotted outline). The cap 22 iscaptively held in place overplug 18 because nozzle 27 functions also as a locking pin. In this operative pos' tion slot 25 is in register with orifice 26. l 5 F After sufiicientfdry powder has been discharged extinguish the tire the pap 22fmay'beir'otated'bac V original position in the horizontal sectionof theT'bayonet; slot 24 to cut-01f thedry powder streamof material.

' Turning to Figs. 7' and 8 there is shown'a modified extinguisher wherein the valve plunger 20 is depressed by means of a moveable hand operated U-shaped squeeze grip plate 29. 4

In this modified form the palm depressible bayonet slotted cap 22 is eliminated and the plunger 20X is hingedly secured to the side walls of the U-shaped squeeze grip plate 29 by means of a hinge pin 30 having a pair of hemispherical ends 31 for preventing the pin 30 from falling out. 7

The plunger 20X is further provided with an aperture suitably disposed from the top end thereof and through which a lock pin, for example a cotter pin 32, is disposed. The cotter pin 32 is provided with a wire pull cord 33 so that in the operation of the modification shown in Figs. 7 and 8 the cotter pin is pulled out of the plunger prior to squeezing the plunger downwardly and through dia phragrn 16.

As shown in Fig. 7, the plunger 20X has a passage throughout substantially half its length and solid thereabove, the cotter pin 32 and the hinge pin 30 being disposed in suitably disposed apertures in the solid part of the plunger 20X. The passage of the tubular plunger extends from the beveled plunger cutting edge 21 to a lateral aperture 34 adapted to register with orifice 260i plug 18 when the plunger is fully depressed and in operating relationship with the container 10 for passage of a stream of powder from said container to orifice 26.

The grip plate 29 is journaled at its forward end by means of a swivel pin 35 to a moveable U-shaped lock plate 36 having a substantially flat terminus 37 having an aperture therein through which nozzle 27 passes thereby locking plate 36 to nozzle 27. r V

A compression coil spring 38 is disposed between handle 28 and grip plate 29in punched dimple protruberances formed respectively therein.

In the operation of the modification shown in Figs. 7 and 8 depressing of plate 29 depresses the plunger 20X thereby cutting diaphragm 16 and simultaneously bringing aperture 34 into registry with orifice26 to permit the contents of the container 10 to stream from nozzle 27 and toward'the fire to be extinguished.

This invention has been described by means of an embodiment but clearly. otherembodiments fall within the'scopeof the claimsherein. 7 g 1 @Wejclaimzy lf 'Adr'y powder'fir'e extinguisher a pressure 'resistantcontain'er;having a top aperture; a tubular seat element fha'v'ing" an inner; horizontally disposed circular shoulder; thepaSsag'e of said seat' elem'entbeing threaded from the top to a point in spaced relation to said shoulder,

' saidse'at element having a circular groove in said passage a central pas'sageand a lateral passage'communicating with the plunger passage adjacent the plunger top, said plunger being slidably disposed in the passage of the plug 7 in contact with the plug passage wall, and extending above at the end of said threads and also in suitable spaced relati'onship lto said shoulden's'aid seat element being fixedly secured 'withi'n'the container'aperture'in' a gas tight manner; asyphon tube having-a suitable horizontally t disposed flange atoneiend, said flange disposed upon said circular shoulder of said seat element to completely cover the shoulder area; saidsyphon tube extendingin said container ma suitable point in spaced relationship to the container'bottom; a metal pierceable sealing diaphragm disposed contactingly upon said "syphon' tube flange to completely engage the topfof thesy'phon tube flange; a resilient O-ringtldisposed in said groove of said passage? of said seat element and contacting said seal ing diaphragm completely at "its periphery; a tubular plug having a central smooth wall passage communicating 1 adjacent the plug top with a lateralzpassage leading to the Y plug -exterior surface, said'plug having exterior screw threads atfits bottom terminating at a circular groove in the-bottom periphery of said plug, said plug being forcefullytthreaded into' the threaded seat elementso that the groove ofrthe plug engages'said O -ringin a gas tight manner and further forces said O-ringto engage said seatelement and the sealing diaphragm adjacenttheretolalso in asgas tightmanner; a slidable tubularrplunger having the plug top, said plunger having its lateral passage out of registry with the lateral passage of said plug in nonoperative position, said plunger having a sloped bottom cutting edge disposed suitably .above the sealing 'diaphragm and being of lesser diameter at its base adjacent the cutting edge to prevent jamming-of vthe cut diaphragm metal with the plunger; and means f or placing the lateral passage of said'plung'er intofre'g'is'tration withtheflate'ral passage of gsaid plug yvith substantiallyi a simultaneous cutting of said sealing diaphragm,

- 2. The apparatus of claim lWhrin the means for a placing the said lateral passages in registry comprises a 2 bottom handle secured fixedly to said plug, a toprhandle secured swingably adjacent one end to the plunger portion 7 extending above said p u a nozzledisposed in th'ellateral passage of said p lug, ap'lapertured lock plate svvingablj secured to the end ofthe top swingable handle with said nozile disposed in said aperture of said lock plate anda compression spring disposed between said topand said 7 bottom handles to continuously urge them apart from'one anothe n 7' 7 Q References Cited in the file of this patent u UNITED STATES YPAT ENTS i Rotheim 2 Apt- 7 1-931 i I z 

